Electric motor drive and control for wheel chairs



Sept. v20, 1949. H. R. PETERSON ET AL 2,482,203-

ELECTRIC MOTOR DRIVE AND CONTROL FOR WHEEL CHAIRS Filed Aug. 16, 1946 3 Sheets-Sheet l INVENTOR. 7a HAROLD R. PETERSON FRED H. JOCK jkgw l T FORNEY Sept. 20, 1949. H. R. PETERSON ET AL 2,432,203

ELECTRIC MOTOR DRIVE AND CONTROL FOR WHEEL CHAIRS Filed Aug. 16, 1946 3 Sheets-Sheet 2 [N V EN TOR.

FRED H. JOCK BY ATTORNEY HAROLD R. PETERSON Sept. 20, 1949. H. R. PETERSON ET AL 2,482,203

ELECTRIC MOTOR DRIVE AND CONTROL FOR WHEEL CHAIRS Filed Aug. 16, 1946 5 Shee'ts-Sheet 3 INVENTOR. R. PETERSON JOCK Patented Sept. 20, 1949 UNITED STATES PATENT Escortrenown DRIVE AND oonrnon FOB WHEEL CHAIRS Harold R. Peterson and Fred a. Jock; Flint, Mich. Applicant Augustis, 1946, said No. 690,847

3 Claims.

, This invention refers to awheel chair and par]- ticularly to a type thereof which is motor driven and fully controllable by a single handlefelenrent. While motor drivenwheel [chairs have been provided in the past there hasnever, for one; realson, or another, beenpro'vi'ded one whichisfdf sufficient simplicity to be easily and. safely handled by the average wheel chair. occupant. Usually the controls havebee'n too complex, or too numerous, ,for the. wheel chair occupant to handle effectively, and hence in prete t such Wheel chairs have often. been a source of con} fusion and, danger rather than a source of ease and comfort.

Therefore, it,is hereinproposed top rovidefa wheel chair in which all functions ofst'artin'g and stopping steering, andbraking are. controlled solely through movement of a single, handle.

Accordingly, a principal object. of. the. invention is to provide a wheel fchairfofthe motor driven type, wherein all. operations o'f ..st'q'ppin g and starting the motor, controlling 'its. speed, Steering and braking are all performed through the manipulationof asingle controlhandle,

A further object of the inventionis to provide a wheel chair of the motor driven type, as aforesaid, in which the controlling operation from such handle will be, definite and positive and will beiree from confusion.

p A further object of theinvention to provide 1 a motor driven wheel chair as aforesaid i'nwhifch the parts are of suificient simplicity to make pos sible economical fabrication.

A further object ofthe invention is to provide a wheel chair of the motor driven type as aioresaid in which the parts are of sufiicient simplicity that they will not require precise or complex ad,- justm'ent and hencewill not readily get out 'of order or preferred adjusted position. v

A further object of the inventionis to pro: vide a wheel chair of the type aforesaid which will be strong and sturdy in order to withstand long and rigorous use.

Further objects and purposes of the invention will be apparent to persons acquainted with equipment of this type upon reading the following disclosure and inspecting the accompanying drawings.

In the drawings:

Figure 1 presents a side elevation view of the wheel chair.

Figure'z is an elevation, partially section, the section portion being taken on line II-I-I of Figure 4. Figure 3 is a fragmentary bottom-planview, partially in section, the section being taken on line IIIHI of Figure 1.

Figure 4 is a rear elevation of the wheelchair. Figure 5 is a detail on an enlarged scale showing a front view of the motor and driving wheel assembly.

. 2 Figured is an enlarged detail of the control column. taken in central section of said column in which, however, the upper part of the fi ure has been rotated 90 with respect tothe lower part of the figure for a better showing of the functional relationships of the parts.

Figure 7.isa schematic wiring diagram. I Figure. 8 is a section taken on the line VIII- VI II in Figure 5. N

In providing a wheel chairmeetingthe objects and purposes above set forth,we have pro vided a chair supported upon two forward wheels of fixed direction and. one rearward, swivelly mounted, wheel which comprises boththe driving, or traction, wheel and the steering wheel. Held above said driving wheel by a suitable support is the motor driving mechanism and the braking mechanism, all controlled from the controlpost mounted in a forward corner of the chair where it is readily available for operation. Referring now in detail tov the drawings, in Figure 1 there is shown in general a wheel chair which may be of anyconvenient construction, which here appears as comprisin a seat I having arms-Z and 3,.a back}! for easy adjustment with respectto said seat by any convenient and conventional means (not shown) and a supporting. frame 5 comprising, a. seat-supporting portion B, fr n whe lsupportin p ts a tt mand rear members 8 and 8a. and back and arm ,sup porting members 9' and 9a. A foot supporting part IE! and its associated frame Il may also be provided according to conventional construction. The front wheels l5 and I6 are mountedon an axlel! which. is supported on the frame by springs I8 and, I9. At the back of thechair, a pair of frame members, preferably tubular, 20 and 2| extend inwardly of the chair from the bottom and rear frame members 8 and 8a and; support the swivel mounting member 22. This member comprises a, vertically arrangedbearing through which exetendsthe swivel pin 23 rotatably positioned therein. On the upperend of. said p;in;, there is fixed sprocket 2G for purposes appearing hereinaft rtthe icwer nd of aid swivel n he e mounted a conventionalyokecomprisedoi; a. ho i o tal member an two. v rtical members 2t and 21. Atthe lower end ,Qf the .yerticalwheel supporting member '25 is held the balance pin Mounted substantially horizontally on said balancepin is a horizontal wheel supporting member 3] to which on one end is rotatably mounted one end of the wheel shaft 32 and on the other end is affixed one end of a relatively heavy coil spring The other end of said springisaffixed at a l. to a part of the wheel supportin member 25. The drive wheel 35 is rotatab r lm um'eee he. haw A h ewhee mounting elements last described have counter parts on the other side of the swivel wheel 35,

which parts are designated by the numerals a to 34a inclusive. The extended axis of the swivel pin 23 passes through the rotative axis of the drive wheel 35.

Mounted on and fixedly with respect to the swivel wheel 35 is a driving sprocket 36 located as best shown in Figure 5 between the supporting member 26 and the swivel wheel. Placed between the driving sprocket and the support 26 on the one side, and between the driving wheel and the support 21 on the other side, are a pair of motor supporting elements 40 and 4| themselves supported at their lower ends 42 and 43 on parts 32 and 32a of the swivel wheel shaft. To hold the motor fixed with respect to the mounting post bearing 22 there is provided, as best shown in Figure 8, a pair of pins 44 on each of the wheel supporting members 25 and 21, located on the side of each thereof nearest the drive Wheel 35 and placed both above and below the motor supporting elements. Other means may, of course, be readily substituted for this purpose without altering the scope or nature of the invention. The pins may be fixed or include rollers as illustrated.

' Ailixed to the motor shaft is a sprocket 41 which is operatively connecte by a chain 48 to the driving sprocket 36. On an extension of said shaft there is a brake wheel 49 surrounded by a brake band 50. This brake band is fastened at each of its ends to a braking arm 5| at the spaced points 52 and 53. The braking arm is itself pivotally supported at 54, namely, a point between the said points 52 and 53 by a supporting arm 55 mounted in any convenient manner on the motor housing.

Firmly mounted by the bracket 45 to the motor housing is a solenoid whose core 5| is operatively connected to the operating end of the braking arm 5|.- A spring 63 is fastened at any convenient point on the motor support at its one end and is fastened at its otherend to the braking arm in a manner to urge it downwardly. It will be observed that the downward urging of the braking arm by the spring will cause it to turn around the pivot point 54 by which to'draw the brake band 50 tightly around the braking wheel 49. Energizing the solenoid will lift the solenoid core 6| against said spring and release said brake.

At any convenient forward part of the wheel chair there is provided the control post generally indicated at 10. tubular member 1| held by plates 12 and 73 against vertical movement with respect to the seat I' of the wheel chair but permitting rotative movement with respect thereto on the bearings 14 and 75 suitably mounted as convenient. An arm 16 extends sidewardly from the tubular member H, at the end of which arm is pivotally mounted the control arm 11. At a point near the lower end of the said tubular member ll there is a sprocket 18 afllxed thereto in non-rotative rela- This control post comprises a tionship therewith. An operating connection comprising a chain, or a combination of a pair of chain elements and a pair of connecting rods, and indicated generally by the numeral 19, operatively connects the sprocket 18 with the sprocket 24,

whereby actuation of the control arm 11 through the handle in a forwardly and backwardly direction for rotating the tubular member H by which to rotate the sprocket 18 will act through Fixed within said tubular member H are the control rod guides 81 and 82 and 83, the latter being preferably in the form of a threaded plug to close a bottom end of said tubular member and to provide a rest for the spring 84. Said spring surrounds the control rod resting its one end against the plug 83 and its other end against a collar 85 fixed with respect to said control rod, by which the control rod is normally held in its uppermost position. The tension of such spring may be somewhat adjusted by adjusting the position of said plug 83 with respect to said tubular member H. The control member 11 extends through a suitable slot 81 in the tubular member H by which its lower side may rest against the upper end 88 of the control rod 85. Thus downward movement of the control handle 89 will move the control rod 85 downwardly against said spring 84, but release of the downward force on the control handle will enable the spring 84 to move the control rod and said handle again to its uppermost position. An electrical control box 90, usually comprising a resistance rheostat, is affixed below the seat portion l of the wheel chair and has a pivoted operating arm 9| extending from. a pivot point 92 to the lower end 93 of the control rod 85. The control rod is so associated with said control arm, that downward movement of said control rod will move the control arm downwardly and a spring 94 is provided to move said arm back upwardly when said control rod 85 moves upwardly. The strength of this spring 94 is, selected accord ing to the desire ofthe operator and afiords, along with the adjustment provided by the plug 83, ample opportunity to fit to the wheelchair user the amount of total upward resilient urging of the operating handle 80. I

A battery, or batteries, I00 may be provided of convenient and practical type and size, mounted on any convenient means supported by the frame member 8 and its counterpart on the other side of the chain. The battery, or batteries, are connected in any conventional manner to the driving motor 45 through the control box 90. Said box is r constructed and connected in such a manner that When the control arm 9| is in its uppermost position there is no power flowing through the motor, and as the control arm is moved downwardly a progressively greater. amount of power is applied to the motor. The coil of the'solenoidfil! is connected in series with the motor so that it is energized simultaneously with the energizing of the motor and it is-de-energized simultaneously with the de-energizing of the motor. A typical wiring diagram appears in Figure 7. 7

Operation The operation of the foregoing described wheel chair has been indicated above and may be here summarized. With the control handle 80 in its uppermost position as shown in Figure 6; the arm 9| is likewise in its uppermost position and no power is flowing through the motor. As the handle is pressed downwardly it will act on the rod 85 to move the control arm 9! downwardly and supply power to'both the solenoid 60 and to the motor 45. As the power is supplied to the solenoid it will raise the brake arm 5! and release the brake band 50 from its gripping position with respect to the brake wheel 49. Concurrently the motor will be energized. to act through the chain 48 to rotate the driving wheel 35. The chair will thus move forwardly.

75 It issteered from side to side by push n the control handle 80 forwardly or backwardly as above described, by which to rotate the sprocket I8 and through the chain 19 rotate the sprocket 24 which will rotate the pin 23 on its axis and thus effect steering of the chair. When the force depressing the handle 80 is removed, accidentally or otherwise, the springs 84 and 94 will move the control rod 85, and by it the said handle, to its upward position and the spring 94 will return the switch controlling arm 9| to its upwardly position, thus terminating the supply of power to both the motor and the solenoid 60. The solenoid thus being de-energized, the brake spring 63 will pull the braking arm again downwardly to tighten the brake band 50 around the brake drum 49 in the manner above-described. This is not only a convenient but an important safety feature, for the wheel chair is thus brought to an immediate stop and held firmly against further motion whenever its occupant stops pressing downwardly on the control handle. For patients who may possibly become unconscious during operation of the chair, this is a feature of greatest importance.

As a convenient refinement of the foregoing described mechanism, but not essential to the scope of the invention, reversing means may be provided by the addition of a suitable switch to the control box 90 in any conventional and known manner.

Many variations in design details of the wheel chair above disclosed and described will be apparent to those acquainted with equipment of this sort but such details will be included within the scope of our invention excepting as the hereinafter appended claims expressly provide otherwise.

We claim:

1. In a self-propelled wheel chair construction, the combination comprising: a frame having front and rearward ends and a seat supported by said frame; a pair of front wheels supporting the front end of said frame and a vertically swiveled wheel supporting the rearward end of said frame and having an upwardly extending swivel shaft; a battery carried by said frame and a motor driving said swiveled wheel; gear means on said swivel shaft; a hollow control rod tube vertically and rotatably mounted near a front corner of said frame, a control rod within said tube and means contained therein for supporting said control rod for vertically sliding relationship therewith and resilient means associated therewith for urging said rod upwardly; an operating handle on said tube at its upper end for rotating said tube and also contacting said rod for urging it downwardly against the urging of said resilient means; gear means on said tube at its lower end and power transfer means connecting said last-named gear means to said first named gear means; electrical current regulating means having actuating means, said regulating means mounted on said frame in such relationship to said control rod that said actuating means :ill be moved in current increasing direction with downward movement of said rod against said resilient means; means returning said actuating means in current decreasing direction with upward movement of said rod; electrical connecting means operatively associating said battery, motor and regulating means, whereby upward and downward movement of said control rod will regulate the speed of said motor; said parts all being so arranged that horizontal movement of said handle will steer said chair, vertical movement of said handle will control the speed of said chair and upon release of downward pressure on said handle said chair will automatically stop.

2. The combination claimed in claim 1 wherein said handle has means at its one end to facilitate grasping thereof by its user, is pivoted at the other end to the outside of said control tube and contacts the upper end of the control rod at a point intermediate its ends, whereby said handle may be readily lifted to a vertical position to facilitate the entry into, or leaving from, said chair by its user.

3. In a self-propelled wheel chair construction, having a frame havin front and rearward ends and a seat supported by said frame; a pair of front wheels supporting the front end of said frame and a vertically swiveled wheel supporting the rearward end of said frame and having an upwardly extending swivel shaft; a battery carried by said frame and a motor driving said swiveled wheel; gear means on said swivel shaft; and means manually operable by a person sitting in the seat of said chair for steering same and controlling its speed, the improvement in said last named means comprising: a hollow control rod tube vertically and rotatably mounted near a front corner of said frame, a control rod within said tube and means contained therein for supporting said control rod for vertically sliding relationship therewith and resilient means associated therewith for urging said rod upwardly; an operating handle on said tube at its upper end for rotating said tube and also contacting said rod for urging it downwardly against the urging of said resilient means; gear means on said tube at its lower end and power transfer means connecting said last-named gear means to said first named gear means; electrical current regulating means having actuating means, said regulating means mounted on said frame in such relationship to said control rod that said actuating means will be moved in current increasing direction with downward movement of said rod against said resilient means; means returning said actuating means in current decreasing direction with upward movement of said rod; electrical connecting means operatively associatin said battery, motor and regulating means, whereby upward and downward movement of said control rod will regulate the speed of said motor; said parts all being so arranged that horizontal movement of said handle will steer said chair, vertical movement of said handle will control the speed of said chair and upon release of downward pressure on said handle said chair will automatically stop.

HAROLD R. PETERSON. FRED H. JOCK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 598,314 Crowdus Feb. 1, 1898 680,602 Lleb Aug. 13, 1901 751,231 Walters Feb. 2, 1904 1,540,170 Frick June 2, 1925 2,306,042 Custer Dec. 22, 1942 2,399,605 Schroeder Apr. 30, 1946 FOREIGN PATENTS Number Country Date 18,783 Great Britain 1896 529,814 Great Britain Nov. 28, 1940 

